Contactless Infrared Laser PROBE Circuit Analyzer
Original Publication Date: 1987-Jun-01
Included in the Prior Art Database: 2005-Feb-01
The system described uses a focussed spot of infrared (IR) laser light impinged on the back surface of a semiconductor device of an integrated circuit to induce a photocurrent which can be used to analyze the conductive state of the device in the associated circuit. The light- spot location is observed by means of an IR microscope. Because the observation is made from the back surface, there is no interference by surface layers which has inhibited systems using visible light and observations on the front surface. It is well known [1,2] that by shining light on portions of semiconductor devices and inducing photocurrents the conducting or non- conducting state of the device can be observed.